Southwest airplanes are seen on the tarmac at the Fort Lauderdale-Hollywood International Airport. / Joe Raedle, Getty Images

by Charisse Jones, USA TODAY

by Charisse Jones, USA TODAY

United raised one-way ticket prices in all of its Florida markets by $10 on Thursday, excluding its flights that are on sale.

Delta, American and Southwest followed with similar increases on many of their Florida routes. For Southwest, the increase is affecting 16% of the low-cost carrier's markets.

US Airways attempted to bump up one-way fares by $10 on a larger swath of its domestic network, but on Monday rolled the increase back to just the Florida region.

If the broader fare increase by US Airways had been matched by other carriers, Rick Seaney of fare-tracking site FareCompare.com says, it would be been the eighth successful increase of the year.

Airlines have now tried 15 times to bump up the price for a ticket on a domestic flight. Last year, there were 22 attempts, and nine succeeded.

Separately, Southwest's matching the fare increase on many Florida routes makes it likely that regional price bump will stick. Southwest usually sets the pace when it comes to fares, since other airlines don't want to stand out by charging more than that carrier, which flies more domestic passengers than any of its peers.

Airlines have pointed to fluctuating fuel costs as a key reason for raising fares. And they have more power to do it, after winnowing the number of seats and flights available for those who want to fly.

"This is a slow period for travel so it wouldn't be surprising to see the airlines try and sneak in one more fare hike," says Kevin Schorr, vice-president of Campbell-Hill Aviation Group, an airport and airline consulting firm. "Again, they will keep hiking fares until they see a negative response in demand and that doesn't seem to be happening yet."

Travelers flying to several popular destinations this Christmas were already paying roughly 8% more than they did in 2011, according to travel-booking site Orbitz. And New Year's fares are roughly 5% higher. Hotel rooms are also pricier in some cities, Orbitz says. The average room rate in Los Angeles, for instance, is 10% higher this Christmas than last year.